Best Writing & Content AI Tools

Built-in AI writing assistant in Notion for summarizing, translating, and generating content

Enterprise AI marketing content platform with brand voice customization

Started as AI copywriting, now a GTM AI platform automating sales and marketing workflows end to end

World-leading AI translation tool with superior translation quality

The industry-standard AI writing assistant: real-time grammar, rewriting and tone fixes across 500K+ apps and sites; parent company rebranded to Superhuman in 2025, folding in Coda docs and Superhuman Mail as a productivity suite — free tier with 100 AI prompts a month, Pro from $12/month billed annually

Learneo's AI rewriting and grammar toolkit: a multi-mode Paraphraser, AI Detector with Humanizer, Summarizer and translation across 40+ languages in one place, with desktop, mobile and browser extensions everywhere — free tier available, Premium works out to $8.33/month billed annually

A budget-first AI copy generator: 40+ template use cases, 20+ tones plus custom tone cloning and 35+ languages, with the Unlimited plan at just $7.50/month billed annually for unlimited generation — built for cost-sensitive marketing and e-commerce copy

An AI writing tool built for novelists: its fiction-specialized Muse model is rated best-in-class for prose by multiple reviews, and Story Bible runs a full long-form workflow from outline and character cards to chapter-by-chapter drafts — you keep the copyright, from $10/month billed annually

The deep style-analysis 'Storyteller's Toolkit': 25+ writing reports diagnose style, pacing and readability, with AI Chapter Critique, a Virtual Beta Reader and manuscript marketability analysis for novelists, integrated across Word, Scrivener and browsers — free tier available, Premium at $120/year or a $399 lifetime license

AI21 Labs' AI English rewriting assistant: multiple rewrite suggestions, tone switching, shorten/expand, summaries and AI generation in one, available everywhere via Chrome extension and iOS keyboard — free tier offers 10 rewrites/day, Unlimited works out to $6.99/month billed annually